/*
 * Copyright (c) 2010, VeRSI Consortium
 *   (Victorian eResearch Strategic Initiative, Australia)
 * All rights reserved.
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 *     * Neither the name of the VeRSI, the VeRSI Consortium members, nor the
 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS AND CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package versi.vitro.oaiserviceprovider.helper;

import java.util.MissingResourceException;
import java.util.ResourceBundle;

import org.apache.log4j.Logger;

import versi.vitro.oaiserviceprovider.application.LocalPropertyFilePathMaker;

/**
 * Property file reader. Implements singleton pattern.
 */
public class PropertyFileReader {

    /** log4j instance. */
    private static final Logger LOGGER = Logger.getLogger(PropertyFileReader.class);

    /** APPLICATION_PROPERTY_FILE_READER. */
    private static final PropertyFileReader APPLICATION_PROPERTY_FILE_READER = new PropertyFileReader("application");

    /** ENVIRONMENT_PROPERTY_FILE_READER. */
    public static final PropertyFileReader ENVIRONMENT_PROPERTY_FILE_READER = new PropertyFileReader(
	    LocalPropertyFilePathMaker.propertyBundlePath());

    /** resource. */
    private final ResourceBundle resource;

    /**
     * Do not allow any constructor initialisation.
     * 
     * @param resourcePath
     * 
     */
    PropertyFileReader(final String resourcePath) {
	resource = ResourceBundle.getBundle(resourcePath);
    }

    /**
     * Get singleton instance of PropertyFileReader.
     * 
     * @return singleton instance of PropertyFileReader object.
     */
    public static PropertyFileReader getInstance() {
	return APPLICATION_PROPERTY_FILE_READER;
    }

    /**
     * Get the property value by a specific property key.
     * 
     * @param propertyKey
     *            - The specific property key.
     * @return a property value associated with a specific property key.
     */
    public String getValue(final String propertyKey) {
	String value = null;
	try {
	    value = resource.getString(propertyKey);
	} catch (MissingResourceException missingResourceException) {
	    final String message = propertyKey + " not found";
	    LOGGER.fatal(message, missingResourceException);
	    throw new RuntimeException(message, missingResourceException);
	}
	return value;
    }
}
